预热坩埚是为了驱除坩埚内潮气,预热时间为8min。
参考答案:对
下表是部分用电器工作时的电流值.电器A、电器B、电器C可能分别是台灯、计算器或电热水器,则电器______应该是台灯,电器______应该是计算器.
Generally speaking, the harder one works, ____________.
A.the better he gets result
B.The better results he gets
C.He gets better results
D.Does he get better results